A year after she told fans she was diagnosed with a rare neurological disorder called stiff-person syndrome, and seven months after she stopped touring, singer Celine Dion’s health has deterioriated.

The Grammy winner “doesn’t have control of her muscles,” her sister Claudette Dion, told Canada’s 7 Jours.

“There are some who have lost hope because it is a disease that is not (very well) known,” the elder sister said, as reported by the Los Angeles Times. “What pains me is that she has always been disciplined. She’s always worked hard. Our mother always told her, ‘You’re going to do it well, you’re going to do it properly.’”

According to the National Institute of Neurological Disorders and Stroke, stiff-person syndrome “is characterized by fluctuating muscle rigidity in the trunk and limbs and a heightened sensitivity to stimuli such as noise, touch, and emotional distress, which can set off muscle spasms.”

Last year, Celine Dion told her fans: “While we’re still learning about this rare condition, we now know this is what’s been causing all of the spasms that I’ve been having. Unfortunately, these spasms affect every aspect of my daily life, sometimes causing difficulties when I walk and not allowing me to use my vocal cords to sing the way I’m used to.”

This past May, she told her fans she was “so sorry to disappoint all of you once again,” but she had to stop touring in an effort to gain her strength back.

“It’s true that, in both our dreams and hers, the goal is to return to the stage. In what capacity? I don’t know,” Claudette Dion said. “The vocal cords are muscles, and the heart is also a muscle. This is what comes to get me. Because (her condition is a) one out of a million case, the scientists haven’t done that much research because it didn’t affect that many people.”

That lack of research and any treatment, Claudette Dion said, has the family “crossing our fingers that researchers will find a remedy for this awful illness.”

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